Digital Electronics Basics
- Electrical engineering is a professional engineering discipline that generally deals with the study
and application of electricity, electronics and electromagnetism (higher voltages)
- Electronic engineering is a branch of electrical engineering where we work on low voltage devices
such as semiconductors, transistors, diodes, integrated circuits.
- In electronic engineering we study two types of systems: analog and digital system.
Difference between digital and analog system
- Analog system: continuous value is used to denote the information. Analog signals is defined as any
physical quantity which varies continously with respect to time, e.g. apmlifier, ecg, watch, radio,
etc.
- Digital system: information is denoted by a finite sequence of discrete values or digits. Digital
signals is defined as any physical quantity having discrete values, e.g. digital watch, calculator,
bp machine, thermometer, etc.
Advantage of digital system ↓
- Digital system are easy to design because they do not require sound engineering and mathematical
knowledge, uses only switching circuits.
- Storage for long time and processing of information is easy.
- They provide better accuracy and precision.
- Less affected by noise like sound electric field, magnetic field.
- Better modularity and easy fabrication, it means size will be vary small, e.g. IC.
- Less cost.
Importance of digital system
- Digital system have sucha prominent role in everyday life (digital age).
- Digital system used in communication, business, traffic control, space guidance, medical, industry,
science, etc.
Lets try to understand designing of digital device using which we will understand the entire process.
Q- Design a warning system for a car manufacturing company with three inputs light, day, engine?
- Steps to remember
- Understand problem
- Design a truth table
- Write boolean expression
- Minimize boolean expression
- Implement using logic gates
- After making table next step is to write a boolean expression.
- Boolean expression in easy words: we have to remember where we have either 0 or 1.
- Between SOP and POS which is prior?
- Use whichever has the minimun elements.
- But minterms are more friendly so we usually use it.
- Boolean expression ↓
- After making expression we have to make a circuit which should be less costly. To minimize the cost
we use process like K-map, etc.